JP6414447B2 - Intake pipe structure - Google Patents

Description

  The present invention relates to an intake pipe structure having a silencing function.

In a reciprocating engine installed in an automobile (vehicle), in order to reduce the intake noise, an intake pipe structure with a resonator is adopted in the intake pipe that connects the intake opening of the vehicle and the throttle chamber. The effect is used to mute the sound of various frequency components in the intake system.
Most of the resonators are provided on the outer surface of an intake pipe portion that forms an intake passage that guides air to the engine as disclosed in Patent Documents 1 and 2. And it is connected with the intake passage.

By the way, in order to absorb the sound of the specific frequency component of the intake system by the resonator, a resonance frequency for resonating the sound of the specific frequency component is set and attenuated by the resonance effect. That is, sound is diffused and attenuated while reverberating in space. For this reason, the resonator is required to have a considerable capacity in order to obtain a larger attenuation.
On the other hand, the engine room of an automobile in which a resonator is arranged has many space restrictions for accommodating the engine and auxiliary equipment or for the convenience of external design. This restriction tends to be stricter.

For this reason, in the structure in which the resonator is simply provided on the outer surface of the intake pipe portion (Patent Documents 1 and 2), the intake pipe portion itself is large or large, and it is difficult to dispose the resonator in the engine room.
Therefore, as disclosed in Patent Document 3, a structure in which the entire resonator is accommodated in the intake pipe portion, that is, in the intake passage, to be compact has been proposed.

JP-A-8-21323 JP 2002-240534 A JP 2006-17090 A

However, the structure in which the entire resonator is accommodated in the intake pipe portion is likely to increase the airflow resistance of the intake passage, and involves considerable pressure loss. For this reason, there exists a problem which reduces engine performance.
Therefore, an object of the present invention is to provide a compact intake pipe structure having a resonance space of a resonator without increasing pressure loss in the intake pipe passage.

An aspect of the present invention is an intake pipe structure having an intake pipe portion that forms an intake passage that guides air to an engine, and a resonator that absorbs sound of a predetermined frequency component, and the resonator takes the intake pipe portion into the intake pipe A streamlined wall surface portion that protrudes toward the inner surface side of the passage and draws an arc from the upstream end portion to the downstream end portion in the flow direction is formed, and the streamline wall surface portion absorbs sound of a predetermined frequency component. attached cover part to secure the space, of the wall portion of the streamlined, on the wall surface position exiting tension to the most intake passage, have a communication portion for communicating an intake passage and a predetermined space, communicating The section has a slit provided in a streamlined wall surface that extends in a direction intersecting with the flow direction of the intake passage, and the streamlined wall surface portion is connected to the wall surface on the upstream side of the intake passage from the slit. More than the slit length with respect to the direction intersecting the direction Ri is disposed, the air toward the slit was assumed to have an air flow peeling unit for peeling from the walls.

According to the present invention,
1. By partially projecting the resonator into the intake passage, the entire intake pipe structure can be made compact.
2. By forming the wall surface portion projecting into the intake passage in a streamlined manner, the ventilation resistance of the intake passage is improved and the pressure loss is suppressed.

3. By providing a slit extending in the direction intersecting the flow direction of the intake passage on the streamlined wall surface that protrudes most from the inner surface of the intake passage, the distance from the slit to the inner wall surface of the resonator facing the slit is increased. A space for sufficiently diffusing the sound of the passage into the resonator is secured, and a sufficient resonance effect is exhibited.
4). By providing an air flow separation part on the wall surface of the streamline wall upstream of the intake passage from the slit, the air flow toward the slit does not reach the slit, and abnormal noise due to the air flow hitting the opening edge of the slit Occurrence can be prevented. In particular, since the air flow separation portion is arranged with a length equal to or longer than the slit, it is effective for preventing the generation of abnormal noise and brings about high silence.
Therefore, a compact intake pipe structure having a resonance space of the resonator can be provided without increasing the pressure loss in the intake pipe passage.

1 is a partially cutaway perspective view showing an intake pipe structure according to a first embodiment of the present invention. FIG. 2 is a partially cutaway perspective view showing, in an enlarged manner, a low frequency silencer resonator of FIG. 1. FIG. 2 is a side cross-sectional view of the resonator along the line AA in FIG. 1. FIG. 2 is a plan sectional view of the resonator along the line BB in FIG. 1. The plane sectional view showing the important section of the 2nd embodiment of the present invention.

Hereinafter, the present invention will be described based on a first embodiment shown in FIGS.
FIG. 1 shows the entire intake pipe structure with a resonator. The intake pipe structure includes an intake pipe portion disposed between an intake opening portion of a vehicle and a throttle chamber (both not shown), for example, between an intake opening portion (not shown) of the vehicle and an air cleaner (not shown). 3 and a resonator disposed on the inner surface of the intake pipe section 3, here two kinds of resonators, for example, a low frequency component (corresponding to a predetermined frequency component of the present application) as a specific frequency component of the intake system of the engine It is configured by combining a resonator 5a that silences and a resonator 5b that silences a high frequency component (corresponding to a predetermined frequency component of the present application).

  Of these, the intake pipe portion 3 has, for example, a connection portion 7a that can be connected to a vehicle intake opening (not shown) at one end and a connection that can be connected to an air cleaner (not shown) of the engine at the other end. It has a portion 7b, and the connection portions 7a and 7b are configured to communicate with each other through a cylindrical portion 9 having an elliptical cross section, for example. An intake passage 11 is formed in the lumen of the intake pipe portion 3. In the intake passage 11, the air taken in from the intake opening of the vehicle can be guided to the engine.

  The two types of resonators 5 a and 5 b are provided on both sides of the cylindrical portion 9. Specifically, both the resonators 5 a and 5 b are provided opposite to the outer surface portions on both sides in the radial direction across the axis of the cylindrical portion 9. FIG. 3 is a side sectional view of the resonators 5a and 5b taken along line AA in FIG. 1. FIG. 4 is a plan view of the resonators 5a and 5b taken along line BB in FIG. The figure is shown.

  Each of the resonators 5a and 5b has the same structure, and both have resonance chambers 13a and 13b that are predetermined spaces inside. Specifically, the resonance chambers 13a and 13b are formed on the outer surfaces of the peripheral wall portions 9a on both sides in the short axis direction of the cylindrical portion 9 facing each other across the center of the intake passage 11 as shown in FIGS. In addition, for example, a rectangular flat resonance space is formed. The resonance chambers 13 a and 13 b are both provided with an inner peripheral portion projecting into the intake passage 11. Although each part of these resonance chambers 13a and 13b has a difference in size, most of them have the same structure. Therefore, here, the structure of the resonance chamber 13a (for low-frequency component silencing) shown enlarged in FIG. 2 will be described as a representative.

That is, the resonance chamber 13 a has a concave inner portion 14 a disposed in the intake passage 11 and an outer portion 14 b disposed outside the intake passage 11 as shown in FIGS. 2 and 3.
The outer portion 14b has a frame-shaped side wall portion 17b that protrudes out of the intake passage 11 integrally from the side wall portion 16b forming each side of the inner portion 14a. The side wall portion 17b is provided with a rectangular cover portion 17c so as to close the opening. Thus, the resonance chamber 13a, which is a predetermined space, is formed in a rectangular flat box space surrounded by the bottom wall portion 16a and the side wall portion 16b of the inner portion 14a, the side wall portion 17b of the outer portion 14b, and the cover portion 17c. Yes.

That is, the resonance chamber 13a is disposed in the intake passage 11 so that the inside of the square space projects into the intake passage 11 and the remaining outer portion projects outward from the outside of the intake passage 11 (outside the cylinder portion 9). As a result, the protrusion to the outside of the intake passage 11 is suppressed.
A wall surface portion of the resonance chamber 13a that protrudes into the intake passage 11 is formed in a streamlined manner. The streamline shape portion α (streamline plane) has a structure in which the bottom wall portion 16a that forms the bottom of the resonance chamber 13a is streamlined. That is, the streamline shape portion α is a streamlined shape that projects the intake pipe portion 3 to the inner surface side of the intake passage 11 so as to draw an arc from the upstream end portion in the flow direction of the intake passage 11 to the downstream end portion. It is formed by the wall surface.

  Specifically, as shown in FIGS. 1, 2, and 4, the streamline-shaped portion α is configured so that each end on the upstream and downstream sides in the flow direction of the intake passage 11 in the bottom wall portion 16 a is connected to the intake passage 11. Is formed in a streamline shape that draws an arc that gradually separates from the inner surface of the intake passage 11 as the intermediate portion of the bottom wall portion 16a moves away from the end. Thus, the entire wall surface of the bottom wall portion 16 facing the intake passage 11 is formed into a flat streamline shape that follows the flow direction. This streamlined curved surface suppresses the airflow resistance of the intake passage 11. And the cover part 17c is attached to the opening part used as the wall surface part of a box-shaped structure provided with this streamline shape part (alpha), ie, the side wall part 17b end, and the resonance chamber 13a (predetermined space) is ensured.

  In addition, a communication portion 19 that connects the intake passage 11 and the resonance chamber 13a is provided on the bottom wall portion 16a at the wall surface that protrudes most into the intake passage 11, that is, the top of the streamlined surface. The communication portion 19 is formed from a slit 21 that extends, for example, perpendicular to (crosses the direction of) the flow direction of the intake passage 11. The sound in the intake passage 11 is diffused from the slit 21 into the rectangular flat resonance chamber 13a. With the arrangement of the slit 21, as shown in FIG. 4, a distance δ1 from the slit 21 to the wall surface of the cover portion 17c facing the slit 21 is gained, and the intake passage 11 can be formed while being a flat resonance chamber 13a. The internal sound is sufficiently diffused to the end portions (each part) in the resonance chamber 13a, and the sound having a predetermined frequency component is attenuated (absorbed) by the resonance effect.

  Further, among the streamlined wall surfaces formed by the bottom wall portion 16a as shown in FIGS. 1, 2 and 4, the upstream wall surface in the flow direction (the intake passage 11) sandwiching the slit 21 The air flow separation part 23 is provided so that the slit 21 does not receive the influence of the air flow a flowing through the streamlined wall surface. The air flow separation portion 23 has a structure in which, for example, an L-shaped step portion 25 is formed along the width direction of the upstream side wall surface of the bottom wall portion 16 a, which is a direction intersecting the flow direction of the intake passage 11. The step portion 25 is arranged over the entire width direction of the wall surface. Thereby, the step portion 25 is arranged over the length of the slit 21 so as to allow the entire slit on the upstream side of the slit 21. At this stepped portion 25, the air flow a on the wall surface toward the slit 21 is separated from the wall surface so that the air flow a does not go to the slit 21.

The resonator 5a has a capacity of the resonance chamber 13a (capacity of the internal space), an opening area of the slit 21, so that a resonance frequency suitable for suppressing a low frequency component that is a sound of a predetermined frequency component to be silenced is generated. The plate thickness of the bottom wall portion 16a (corresponding to the communication length of the communication portion) is set. That is, a resonator for silencing low frequency components is used.
The remaining resonator 5b has a structure equivalent to that of the resonator 5a, and the resonance chamber 13b capacity (internal space capacity) and the opening area of the slit 21 so as to generate a resonance frequency suitable for suppressing high frequency component sounds. The plate thickness of the bottom wall portion 16a (corresponding to the communication length of the communication portion) is set. That is, a resonator for silencing high frequency components having different frequencies to be silenced is used.

The resonator 5b is substantially the same as the resonator 5a except that the resonator chamber capacity, the slit opening area, the plate thickness of the bottom wall portion 16a, and the step portion 25 are not present. The same reference numerals and similar reference numerals are assigned, and the description thereof is omitted.
According to such an intake pipe structure, air taken in from an intake opening (not shown) of the vehicle is guided to a throttle chamber (not shown) of an engine (not shown) through an intake passage 11 and an air cleaner (not shown). .

  At this time, the high-frequency component and low-frequency component of the intake sound in the intake passage 11 enter the resonance chambers 13a and 13b through the slit 21 of the resonator 5a and the slit 21 of the resonator 5b, respectively, and resonate with the inner surface of the cover portion 17c. However, it diffuses to each part in the resonance chambers 13a and 13b. And according to the resonance frequency set by each resonator 5a, 5b, the sound of the specific frequency component which is a sound of a predetermined frequency component is attenuate | damped (absorbed) by the resonance effect.

This intake pipe structure can exhibit a sufficient resonance effect while being compact.
That is, since the resonators 5a and 5b partially protrude into the intake passage 11 and are arranged on the outer surface of the intake pipe section 3, the protrusion to the outside of the intake pipe section 3 is suppressed. Thereby, the whole intake pipe structure becomes compact.
In particular, since the wall surfaces of the resonators 5a and 5b projecting into the intake passage 11 are formed in a streamline shape, an increase in ventilation resistance of the intake passage 11 can be suppressed. Thereby, the pressure loss caused by the overhanging of the resonators 5a and 5b is suppressed.

  Moreover, since the slit 21 (communication portion 19) is provided at the point of the streamlined wall surface (bottom wall portion 16a) that protrudes most into the intake passage 11, the slit 21 is located at the position of the slit 21. The distances δ1 and δ2 to the inner surfaces of the cover portion 17c facing each other (wall surfaces of the resonance chambers 13a and 13b) can be earned, and the sound of the intake passage 11 is sufficiently diffused to the inner corners of the resonators 5a and 5b by reflection. Even though the resonance chambers 13a and 13b are flat, a sufficient resonance effect is exhibited.

Therefore, the intake pipe structure can be made into a compact structure having the resonance space of the resonators 5a and 5b without increasing the pressure loss in the intake pipe passage 11.
Moreover, by providing the stepped portion 25 (airflow separation portion 23) on the upstream wall surface from the slit 21 (communication portion 19), the air flow a toward the slit 21 along the streamlined wall surface as shown in FIG. Since it is peeled off by the step portion 25 and goes in the other direction, it is possible to prevent the generation of abnormal noise called whistling sound due to the airflow hitting the opening edge of the slit 21 without reaching the slit 21. In particular, since the step portion 25 is arranged with a length equal to or longer than the slit 21, it is effective for preventing the generation of abnormal noise and can provide high silence.

Further, each part of the resonators 5a and 5b has a capacity of the resonance chamber 13b (capacity of a predetermined space), an opening area of the slit 21, and a plate thickness ( slit of the bottom wall part 16a) so that a resonance frequency with respect to a sound having a predetermined frequency component is generated. Is equivalent to the communication length), and a sufficient resonance effect can be expected.
FIG. 5 shows a second embodiment of the present invention.

This embodiment is a modification of the first embodiment, in which a streamlined resonance chamber structure is employed only for the resonance chamber 13a for silencing low-frequency components, or the airflow separation portion 23 protrudes from the streamlined wall surface. It is formed from the strip 27. Incidentally, the protrusion 27 is formed along a direction orthogonal to the flow direction of the intake passage 11.
Even with such a structure, the same effects as those of the first embodiment can be obtained. However, in FIG. 5, the same parts as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  It should be noted that each of the above-described embodiments and combinations thereof are merely examples, and that addition, omission, replacement, and other modifications of the configuration can be made without departing from the spirit of the present invention. Needless to say. Further, the present invention is not limited by the embodiment, and it is needless to say that the present invention is limited only by the “claims”. In the above-described embodiment, the present invention is applied to the intake pipe structure in which two types of resonators are arranged. However, the present invention is not limited thereto, and the present invention may be applied to an intake pipe structure in which one type of resonator is arranged. . In the above-described embodiment, a rectangular flat resonator is used. However, other shapes of resonators may be used. In the above-described embodiment, an example in which the resonator is disposed between the intake opening portion of the vehicle and the air cleaner has been described. However, the present invention is not limited thereto, and the resonator may be disposed between the intake opening portion of the vehicle and the throttle chamber. Any position may be used.

3 Intake pipe portion 5a, 5b Resonator 11 Intake passage 13a, 13b Resonance chamber (predetermined space)
16a, 16b Bottom wall part, side wall part (wall surface part)
17c Cover part 21 Slit (communication part)
25, 27 Stepped part, ridge part (air flow separation part)
α Streamline shape part α (streamline surface)

Claims (2)

An intake pipe structure having an intake pipe portion that forms an intake passage that guides air to the engine and a resonator that absorbs sound of a predetermined frequency component,
The resonator is
The intake pipe portion extends to the inner surface side of the intake passage to form a streamlined wall surface portion that draws an arc from the upstream end portion in the flow direction to the downstream end portion, and the streamline wall surface portion includes the predetermined line portion A cover that secures a predetermined space to absorb the sound of the frequency component of
Of the wall portion of the streamlined, most on the wall surface position exiting tension to the intake passage, have a communication portion for communicating the predetermined space between the intake passage,
The communication portion has a slit extending in a direction intersecting with a flow direction of the intake passage provided on a streamlined wall surface,
The streamline wall surface portion is disposed on the wall surface upstream of the intake passage from the slit over the slit length with respect to the direction intersecting the flow direction of the intake passage, and the air flowing toward the slit An air intake pipe structure having an air flow peeling portion that peels from the wall surface . 2. The resonator according to claim 1 , wherein a capacity of the predetermined space, an opening area of the slit, and a communication length of the slit are set so that a resonance frequency with respect to the sound of the predetermined frequency component is generated. Intake pipe structure.

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